The high prevalence of overweight and obesity among children in this country, particularly those from minority backgrounds and living in poverty, has become a major national concern. In the majority of cases, the obesity epidemic, caused by poor diet and physical inactivity, is preventable. Promoting positive eating behaviors in childhood is important because dietary behaviors developed during this time tend to track into adulthood. This developmental trajectory highlights the importance of targeting healthpromotion programs for young children who are not yet overweight, and as such, schools are an important venue for activities to occur. Prior school-based nutrition education research has demonstrated how challenging it is to achieve enduring behavior change and to impact biological measures of obesity. This is not surprising, given the oxic enviornment in this country that is well suited for the development and maintenance of obesity. Despite these challenges, school-based obesity prevention efforts are important to pursue. The purpose of this study is to further school-based nutrition education research by developing and evaluating a multi-component, theoretically-grounded, intensive 5-A-Day health promotion program that will follow a cohort of children from kindergarten through fourth grade. This program will be implemented in 6 schools in the Boston Public School District. All of the schools are affiliated with the Athletes in Service (AIS) AmeriCorps program, and have college student athletes working in them full time to promote physical health and academic success. The school staff and AIS staff will collaborate to implement the classroom, lunchtime, afterschool, and family components of this program. The outcome evaluation will examine changes in students' nutrition knowledge, eating behaviors, eating preferences, and biological indicators of obesity and overweight and impact of the family component on availability and accessibility of fruits and vegetables at home over a 5 year period.